Optical and thermal performance of parabolic trough collectors. Robert Pitz-Paal, Institute of Solar Research

Transcription

1 Optical and thermal performance of parabolic trough collectors Robert Pitz-Paal, Institute of Solar Research

2 Chart 2 > Eurotherm No. 98 > Pitz-Paal Overview 1. Motivation for Improving Performance 2. Qualification of Concentrators 3. Qualification of s 4. Conclusions

3 Chart 3 > Eurotherm No. 98 > Pitz-Paal 1. Motivation Improved Performance by Proper Implementation of Construction - Solar field has a high share of the total investment - It is a long-term investment - It is of big extent (corrections are expensive) - Yearly plant output strongly depends on optical quality of collector field - Measurements showed that without proper quality assurance 3-10% and in some cases even more of the field performance can be lost - Quality assurance and final acceptance tests of collector fields are necessary for control of subcontractors and warranty claims Quality assurance of collector field assembly is indispensable and makes economic sense

4 What is a parabolic trough?

5 Chart 5 > Eurotherm No. 98 > Pitz-Paal 1. Motivation Efficiency Chain, Example: Parabolic Trough Example ANDASOL: 1% less optical quality means for investors: 0.5 million less revenues per year 10 million less revenues per lifetime

6 Chart 6 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators Possible Concentrator Errors Microscopic surface errors (roughness, deterioration, scratches, ) Macroscopic surface deviations (waviness, mirror contour errors, deformations, structural errors, ) Positioning of the receiver tube (position of supports, bending of tube, ) Tracking errors (tracking, module alignment, collector torsion, ) microscopic surface errors positioning error of absorber tube tracking error missing ray n ideal mirror contour error (Sun Shape) Slide 6

7 Chart 7 > Eurotherm No. 98 > Pitz-Paal Intercept depends on component quality and alligenement quality

8 Chart 8 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot Parabolic Trough Central

9 Chart 9 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators Deflectometry X α u α u n u z f x α 1,u α 1,l camera Z d abs α l n l α l reflector d cam

10 Chart 10 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators Deflectometry Image Acquisition Slide 10

11 Chart 12 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators Deflectometry Result Focus deviation in mm of reflected ideal rays

12 Chart 13 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Deflectometry Calculation Result Local intercept factor in percent with consideration of degraded sunshape

13 Chart 14 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot Materials Parabolic Trough Central

14 Chart 15 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Photogrammetry: Collector Shape and Deformation From photos to coordinates Image acquisition: several photos of measurement object are taken form different angles Point recognition: clearly recognizable points of object are determined in all photos Evaluation: calculation of 3D point geometry via initial orientation, intersection and bundle adjustment Scaling: inclusion of known distances between targets Result: all object coordinates, camera positions and orientations together with their precisions are known

15 Chart 16 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Photogrammetry: Collector Shape and Deformation Object Preparation Results - 3D Coordinates - Coordinate Deviations - Angle Deviations Shape and Deformation Studies

16 Chart 17 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer Parabolic Trough Central

17 Chart 18 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators Deflectometry Measurement Setup for Heliostats Camera Projection screen Heliostat r α α n i Projector Tower

18 Chart 19 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators Deflectometry Measurement Setup for Heliostats Camera Projection screen Heliostat r α α n i Projector Tower

19 Chart 20 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Deflectometry Reflected Patterns in Heliostat horizontal vertikal

20 Chart 21 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Deflectometry Results Heliostat CESA-1, PSA Slope deviation in x-direction in mrad Slope deviation in y-direction in mrad Results Measured Mean on heliostat deviations focal length level: RMS slope deviation adjustments measure for of focal facet length tilt = 1.98 mrad Heliostat design focal length canting = m Measured focal length = m 21

21 Chart 22 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Deflectometry Results Heliostat CESA-1, PSA Slope deviation in x-direction in mrad Slope deviation in y-direction in mrad Results Measured Mean on heliostat deviations focal length level: RMS slope deviation adjustments measure for of focal facet length tilt = 1.98 mrad Heliostat design focal length canting = m Measured focal length = m 22

22 Chart 23 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Deflectometry Raytracing Heliostats CESA-1, PSA - STRAL, DLR-Raytracing program which can Use Deflectometry Results - Code Validation by of a Group of Heliostats with Blocking and Shading - Comparison with Flux Measurement 23

23 Chart 24 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Deflectometry Raytracing Heliostats CESA-1, PSA Flux Measurement Detailed of Solar Flux Possible by Using Deflecometry Data 24

24 Chart 25 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer Parabolic Trough Central

25 Chart 26 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Photogrammetry: Heliostat Shape and Deformation Object Preparation targets on 12 facets (18 each) Photogrammetric measurement - 9 orientations with different elevations (0,10,20,30,40,50,60,70,80,90 ) - 20 photos for each orientation Measurement uncertainty mean over 9 orientations: - σ=0.3 mm - max = 0.6 mm

26 Chart 27 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Photogrammetry: Heliostat Shape and Deformation Measured displacements between 10 and 90 : Photogrammetry (z-deviation) - = 1.1±1.9 mm - max < 5.5 mm

27 Chart 28 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry, Laser-Tracker Parabolic Trough Central

28 Chart 29 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical QDec: Deflectometry Systems for Mirror Panels & Modules QDec: Automated System for Horizontal and Vertical Mirror Panels QDec-M: Automated System for 12m-Collector Module 29

29 Chart 30 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical QFoto: Photogrammetry Setup for Collector Structures Moving Camera Moving Camera Structure to be measured QFoto: Automated System for Collector Structures QFoto-Module Quality Report

30 Chart 31 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry, Laser-Tracker Photogrammetry, QFoto Laser Tracker QFly Deflectometry, Flux Density Parabolic Trough Central

31 Chart 32 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators optical Collector Field Shape Measurement: QFly a) Airborne camera vehicle during a test flight at KONTAS test facility (PSA) b) Automatic creation of flight routes (DISS, PSA) c) Photogrammetric determination of camera and collector position - System successfully validated for single module (against TARMES and Photogrammetrie) - Measurement uncertainty: local slope deviation.: mrad RMS whole module: ca. 0.1 mrad - Up scaling to complete solar fields [mrad] d) Slope deviation measured by QFly for KONTAS collector

32 Chart 33 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry, Laser-Tracker Photogrammetry, QFoto Laser Tracker QFly Deflectometry, Flux Density SAPHIR Deflectometry Flux Density Flux Density Measurement Parabolic Trough Central

33 Chart 34 > Eurotherm No. 98 > Pitz-Paal 2. Qualification of Concentrators / s optical Flux Density Measurement Flux Measurement with Moving Bar Heliostat Beam Characterization by Flux Measurement - Canting - Tracking Errors Flux Measurement on Surface Flux Density by Raytracing-

34 Chart 35 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry, Laser-Tracker Photogrammetry, QFoto Laser Tracker QFly Deflectometry, Flux Density SAPHIR Deflectometry Flux Density Flux Density Measurement Parabolic Trough ThermoRec, KONTAS, ElliRec, Mechanical Prop. OptiRec, Central

35 Chart 36 > Eurotherm No. 98 > Pitz-Paal 3. Qualification of s thermal Qualification - ThermoRec Measurements: - Standardized Component Qualification - Laboratory Measurement of Thermal Losses - Principle: Electrical Heating = Heat Loss Features: - Internal Electric Heating - End Heaters for Homogeneous Temperature Profile - Temperature Measurement of Absorber inside Glass Envelope End Caps Surface - Calculation of Axial End Losses (~3%) and Correction of Power

36 Chart 37 > Eurotherm No. 98 > Pitz-Paal 3. Qualification of s optical Qualification - ElliRec Measurements: - Standardized Component Qualification for Comparative Measurements - Laboratory Measurement of Optical Performance Measurement Principle: - Heating by Metal-Halide Lamps and Elliptical Concentrator - No Thermal Losses, as Ambient Temperature - Measuring Flow Rate of Water - Measuring Temperature Increase (ΔT ~ 7 K) Absorbed Power - Exact Lamp Power unknown, but constant Comparative Measurements to one Virtual 70-mm Master

37 Chart 38 > Eurotherm No. 98 > Pitz-Paal OptiRec: 2nd generation test bench for Optical Method: - similar to ElliRec Goals: - improve long term stability of optics and reproducibility - facilitate replication standardization - improved handling - shorter measurement time - smaller dimensions Status: - operational since early high reproducibility of the measurement of ~ ± 0.2 (1σ) shown - compatibility with ElliRec shown

38 Chart 39 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry, Laser-Tracker Photogrammetry, QFoto Laser Tracker QFly Deflectometry, Flux Density SAPHIR Deflectometry Flux Density Flux Density Measurement Parabolic Trough ThermoRec, KONTAS, ElliRec, Mechanical Prop. OptiRec, Central

39 Chart 40 > Eurotherm No. 98 > Pitz-Paal 3. Qualification of Concentrators & s optical & thermal KONTAS Test Bench at PSA Measurements: - Standardized Component Qualification - On-Sun Measurement of Optical and Thermal Efficiency - Component Performance Features: - Rotative test-platform - Max. Collector Length: 20 m - Active Temperature Control - Heat Transfer Fluid: Syltherm Operation Temperature: 400 C - Mass Flow: <6 kg/s - High Precision Meteo Station - Redundant Calibrated PT-100 Temperature control unit Eurotrough 12m 23 m

40 Chart 41 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry Laser-Tracker Photogrammetry, QFoto Laser Tracker QFly Deflectometry, Flux Density SAPHIR Deflectometry Flux Density Flux Density Measurement Parabolic Trough Central ThermoRec, KONTAS, ElliRec, Mechanical Prop. OptiRec, Efficiency Meas. Several manufacturing specific quality control measures Several manufacturing specific quality control measures

41 Chart 42 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry Laser-Tracker Photogrammetry, QFoto Laser Tracker QFly Deflectometry, Flux Density SAPHIR Deflectometry Flux Density Flux Density Measurement Parabolic Trough Central ThermoRec, KONTAS, ElliRec, Mechanical Prop. OptiRec, Efficiency Meas. Several manufacturing specific quality control measures Several manufacturing specific quality control measures QFly-IR Screening Measure. PARESO HCE Field Meas. Mobile Test Units, Bypass Efficiency Meas.

42 Chart 43 > Eurotherm No. 98 > Pitz-Paal Qualification in Different Phases Phases Objects R&D Phase Production Phase O&M Phase Prototypes Mass Product Commissioned Plant Concentrator Parabolic Trough Coll. Heliostats TARMES Deflectometry Photogrammetry Inclinometer, V-Shot SAPHIR Deflectometry, Photogrammetry, Inclinometer QDec-M Deflectometry QFoto Photogrammetry Laser-Tracker Photogrammetry, QFoto Laser Tracker QFly Deflectometry, Flux Density SAPHIR Deflectometry Flux Density Flux Density Measurement Parabolic Trough Central ThermoRec, KONTAS, ElliRec, Mechanical Prop. OptiRec, Efficiency Meas. Several manufacturing specific quality control measures Several manufacturing specific quality control measures QFly-IR Screening Measure. PARESO HCE Field Meas. Mobile Test Units, Bypass Efficiency Meas.

43 Chart 44 > Eurotherm No. 98 > Pitz-Paal Conclusion - Optical quality of components and their alignment are critical for the commercial success of CSP plants - High quality measurement systems on component and subsystem level exist and are partly transferred to industry - Measurement systems together with Ray tracing and Finite Element Tools improve the understanding of the system and allow for optimization - We feed our experience on optical and thermal performance measurements into standardization initiatives - In situ performance and degradation measurements is one important subject for further development

44 Final Quality Inspection Procedure